There are several different accepted ways to attach a wood sill plate to the top of a foundation wall or slab. One way is to set threaded anchor bolts into the concrete foundation and pour the uncured concrete around the bolts. Holes are then drilled in the sill plate and the plate is then set on the foundation with the anchor bolts protruding through the openings in the sill plate.
Several sheet metal connectors have been designed to replace or provide alternatives to using threaded anchor bolts to connect the sill plate or mud sill to the foundation. Examples of such sheet metal anchors are found in U.S. Pat. Nos. 3,889,441, 3,750,360, 4,413,456 and 4,739,598. U.S. Pat. Nos. 3,889,441 and 3,750,360 are designed with a pair of arms which protrude on either side of the sill plate. The arm on the inner side of the plate, like an anchor bolt placed in the foundation can interfere with the process of screeding and trowling the slab. The present invention is similar to U.S. Pat. Nos. 4,413,456 and 4,739,598, and improves upon them.
The present invention has been designed so that multiple anchors can be spaced along the edge of a foundation with the same spacing that would be used with two of the more common anchor bolt sizes for anchoring a mud sill, specifically anchors bolts having a diameter of either ½″ or 5/8″. That is to say, the mud-sill anchor of the present invention is strong enough to replace a typical, commercially used anchor bolt of either ⅝″ or ½″ diameter set in the same concrete foundation.